Under the terms of a 2015 Joint Comprehensive Plan of Action (JCPoA) deal which Washington unilaterally abrogated in 2018 under former president Donald Trump, some sanctions were due to be lifted on October 18 under the terms of a so-called sunset clause.

But in a joint statement from their respective foreign ministries, Britain, France and Germany noted Tehran's "non-compliance" and underlined their commitment to ensure the country does not obtain a nuclear weapons capacity.

"In direct response to Iran's consistent and severe non-compliance with its JCPoA commitments since 2019, the governments of France, Germany, and the United Kingdom intend to maintain nuclear proliferation-related measures on Iran, as well as arms and missile embargoes, after JCPoA Transition Day on 18 October 2023," a statement read.

The statement said the decision was fully compliant with the JCPoA, given continued Iranian "non-compliance" and given that "Iran has refused opportunities to return to the JCPoA twice and has continued to expand its programme beyond JCPoA limitations and without any credible civilian justification," taking its stockpile of enriched uranium to more than 18 times the amount permitted under the deal.

The ministries at the same time stressed their "commitment to finding a diplomatic solution" and added the decision would be reversed if Iran fully implemented its JCPoA commitments.

A British Foreign Office statement noted that "alongside our French and German partners, we have taken a legitimate and proportionate step in response to Iran's actions."